Stephen Strasburg always pitches under a spotlight, but Saturday took the mound under more scrutiny than usual. After his last start, Monday night in Atlanta, Manager Davey Johnson caused alarm by saying Strasburg had “tightness” in his forearm. The next day, General Manager Mike Rizzo scuttled any notion that Strasburg was dealing with an injury. Across the league, scouts noticed a glitch in Strasburg’s delivery, saying his front arm was pulling the rest of his body out of sync. Saturday, the speculation ceded to Strasburg’s performance. He backed up his insistence he was fine, showing no signs of physical strain. Strasburg threw 95 pitches over seven strong innings, and if you could remove two of them, he may have yielded zero runs rather than four. In the Nationals’ 5-4 win over the Pirates, Strasburg mixed excellence and inconsistency. The erratic delivery and command of his fastball arose, but he also struck out eight and walked only one. Strasburg dominated at times, flashing a change-up in the high-80s that could start over the edge of the plate and dart several inches out of the zone. But he lacked precision with his fastball, which hummed between 93 and 97 miles per hour. He hit two batters with his fastball, missing his target by more than usual. And he also fired two heaters into the center of the strike zone, which Starling Marte and Clint Barmes turned into the two-run homers that accounted for all of Pittsburgh’s runs. “I was happy,” Strasburg said. “I obviously gave up a couple homers, but I was able to get through the seventh. I feel like in the past, if I gave up that many runs I would be up over 100 pitches through six. I just tried to do a better job of pounding the strike zone.” Like in Atlanta, Strasburg ended his start with his strongest inning. In the seventh, knowing his spot in the lineup would come up in the top of the eighth, Strasburg induced two weak grounders and struck out Marte on three pitches, whiffing him with a curveball down and away.